Compressor for pulsator systems



COMPRESSOR FOR PULSA'I'OR SYSTEMS Filed May 18, 1942 Wren r02 22:6. 4. ai /4&5: 475414420 Arrows 5Y5.

Patented Oct. 17, 1944 UNITED STATES PATENT OFFICE COMPRESSOR FOR PULSATOR SYSTEMS Charles Ulen Ballard, Inglewood, Calif.

Application May 18, 1942, Serial No. 443,383

16 Claims.

This invention relates to a compressor for pulsator systems, and may be regarded as a continuation-in-part of divisional subject matter disclosed in my copending application Serial No. 298,686, filed October 9, 1939 (now Patent No. 2,287,960).

An object of the invention is to provide a simple, durable, and highly compact compressor construction suitable for use in pulsator systems wherein there are two opposed cylinders within which are reciprocable connected pistons and a liquid is expelled from one cylinder to the motor or actuator of the system while liquid is being returned from the opposite side of the motor or actuator to the other cylinder. A feature of the construction resides in the fact that the design is such that upon relatively small movements of the piston a relatively large volume of fiuidwill be expelled from the cylinder to operate the motor. This is accomplished by employing annular pistons which are reciprocable between concentric inner and outer walls of their respective cylinders and advantageously utilizing the space within the inner walls to house the operating mechanism.

Another object of the invention is to provide a compressor for pulsator systems which is of such design as to enable parts to be readily removed, repaired, inspected, and replaced and wherein a readily accessible means is provided for taking up wear or loose play that may develop.

With the foregoing and other objects in view, which will be made manifest in the following detailed description and specifically pointed out in the appended claims, reference is had to the accompanying drawing for an illustrative embodiment of the invention, wherein:

Figure l is a View in end elevation of the compressor embodying the present invention;

Fig. 2 is a horizontal section taken substantially upon the line 2-2 upon Fig. 1 in the direction indicated;

Fig. 3 is a partial view in vertical section through a portion of the compressor and may be regardedas having been taken substantially upon the line 3-3 upon Fig. 2 in the direction indicated; and

Fig. 4 is a perspective view of one of the keys or splines forming part of the compressor.

Referring to the accompanying drawing wherein similar reference characters designate similar parts throughout, the improved compressor has been primarily developed for use in conjunction with apulsator system that is utilized for steering boats and consequently will be described in conjunction therewith, but it will be understood that it is applicable to pulsator systems generally and that the compressor may be advantageously employed wherever it is desired to expel liquids in predetermined amounts or quantities. The pulsator illustrated is shown as being operable by a steering or handwheel l0 mounted on the end of a rotary screw II that extends axially through a cylinder-providing means, generally indicated at l2. One end of the screw has a shoulder l3 bearing against a thrust bearing l4 that is recessed in one end of the cylinder-providing means I2. The other endof the screw is equipped with a nut 15 adapted to be tightened into engagement with a thrust bearing I'B recessed in the opposite end of the cylinder-providing means. This nut is preferablyen-closed by a dust cap or shield H.

The cylinder-providing means I2 is preferably made up of two opposed parts l8 and I9 fitted together as at 20 having on the exterior thereof companion flange segments 2| that are bolted together. These parts provide at opposite ends opposed cylinders, the outer walls of which are indicated at 22 and 23. Extending inwardly from the .ends of the heads 24 and 25 are cylindrical sleeves 26 and 21 which present on their outer surfaces inner cylindrical walls which are concentric with relation to the outer walls 22 and 23. A double-ended piston is provided which is made up of two'main opposed parts 28 and 29. Each part has a hub portion 30 internally threaded with threads complementary to the threads on the screw ll. Each part also has an outwardly or radially extending web 3| and a longitudinally extending flange 32 which may be regarded as a skirt. Between the webs 3| there are normally positioned thin shims 3|a. Bolts 33 extend through the webs and serve to connect the opposed parts together. By adding or subtracting shims between the webs 3| the portions of the nut on the screw formed by the hubs 29 can be moved toward or away from each other so that these portions which cooperate together to form the nut on the screw will always snugly engage the threads thereon without loose play. Manifestly, if the threads on the screw become worn a shim may be added to provide proper thrust and to take up wear so that the piston at all times will be operable by the rotary screw ll without loose play.

At the ends of the flanges or skirts 32 there are opposed piston heads. These are each in the form of an annular ring 34 faced with a facing formed of rubber or equivalent material. The inner and outer peripheries of these rings are grooved as at 36 and the facings are equipped with corresponding portions that will normally contract or snap into these grooves so as to retain the facings thereon. At their outer ends these facings are equipped with thin tapering flanges 31 similar to those of cup leathers, and serve to form seals between the piston heads and the inner and outer walls of the respective pistons. The facings may also be provided with protuberances 38 engageable with the ends of the cylinders or the heads 24 and 25, respectively, to limit the extreme movements of the piston parts toward their respective heads.

On the backs of the piston heads there are formed cylindrical extensions or skirts 39 that telescope within the flanges or skirts 32. It is unnecessary to attach the heads 34 other than by these cylindrical skirts telescoping within the skirts 32. In fact, it is an advantage to have the pistons unattached to the skirts 32 in that if the quantity of fluid in the conduits leading to and from the outer ends of the cylinders should decrease such as by leakage or by contraction due to a fall in temperature, a receding or retreating piston will not follow its skirt 32 completely but instead will be forced away from the end of its cylinder only to the extent'of the remaining fluid that is caused to enter the cylinder. Consequently if the lines are replenished with fluid under these circumstances it is unnecessary to bleed the cylinder but the replenishing fluid merely serves to take up any play existing between a piston and its skirt 32. Loss of fluid in the lines quickly manifests itself by loose play between a skirt 32 and its piston which is readily discernible in the steering wheel Hi. It will of course be appreciated that normally fluid is maintained in the lines so that there is no lost play between the pistons and their skirts 32. On diametrically opposite sides of the flanges or skirts 32 there are formed grooves or keyways 4D in which are disposed keys or splines 4|. These keys or splines are secured within the cylinders as by cap screws 42 and preferably have central bores 43 formed therein into which are screwed grease cups 44. Grease from these grease cups can be forced into the keys or splines and discharged into longitudinally extending grooves 45 formed on the side faces of the splines. The function of these keys or splines is to prevent the piston from rotating sympathetically with the screw II and by the means above described adequate lubrication is provided at all times.

As will be noted from an inspection of Fig. 2, the hub portions 30 telescope within the sleeves 26 and 21, respectively, and there is preferably a relatively close fit between these parts.

In the heads 24 and 25 adjacent the bottom thereof there are formed passages 46 and tubing or other hydraulic connections are connected to these passages and lead to the motor or driven element of the pulsator system. Thus one tubing from one end of the device leads to one side of the motor and another tubing from the other head leads to the other side of the motor. Consequently, if the piston is moved in one direction liquid in that end of the cylinder is expelled therefrom through the hydraulic connection to the motor. Exhaust fluid from the motor is returned to the cylinder through the other connection.

In the heads 24 and 25 adjacent the top thereof, there are formedbleeding ports 41 in which bleeding valves or needle valves 48 are installed for bleeding the cylinders of the compressor whenever occasion requires.

The operation and advantages of the improved compressor are as follows. If the steering wheel or hand wheel I0 is rotated in one direction the rotary screw is rotated thereby causing the piston to be moved toward one end of the cylinderproviding means 12 expelling fluid from that end through its outlet passage 46 and through the tubing to the motor. The returning fluid that is returned from the motor to the other end of the compressor fills the cylinder space therein and keeps the annular head 34 tight against its skirt 32. During operation of the piston by the handwheel the hub portions 30 telescope freely within the cylindrical portions 26 and 21 and are somewhat guided or steadied thereby. Leakage around the piston heads is effectively prevented by the tapering flanges 31 on the piston facings 36. It will be noted that a relatively small amount of rotation of the rotary screw causes a relatively large volume of liquid to be expelled inasmuch as the piston that is moved is a large annular area around the sleeves 26 and 21. The space within the sleeves is advantageously utilized to house the ends of the rotary screw ll. Consequently, by this arrangement although the compressor is capable of handling large volumes it nevertheless is quite compact in construction. All parts are readily available for inspection, repair, and replacement purposes whenever this may be required.

Various changes may be made in the details of construction without departing from the spirit or scope of the invention as defined by the appended claims.

I claim:

1. A compressor for pulsator systems and the like comprising means providing opposed annular pistons, means providing opposed cylinders therefor having concentric inner and outer walls between which the pistons are reciprocable, there being passages leading to and from the cylinders, and means for reciprocating the pistons extending longitudinally within the inner concentric walls of the cylinders.

2. A compressor for pulsator systems comprising means providing opposed cylinders, pistons reciprocable therein, a rotary screw, the pistons being connected to a transversely divided nut fitting about the screw the portions of which may be tightened toward each other to take up wear, there being passages leading to and from the cylinders, and means for rotating the rotary screw.

3. A compressor for pulsator systems comprising a rotary screw, means providing inner cylinder walls about the screw, means providing outer cylinder walls concentrically around the inner cylinder walls and opposed pistons threadedly connected to the screw reciprocable between the inner and outer cylinder walls, there being passages leading to and from the outer ends of the cylinders.

4. A compressor for pulsator systems comprising a rotary screw, means providing inner cylinder walls about the screw, means providing outer cylinder walls concentrically around the inner cylinder walls and opposed pistons threadedly connected to the screw reciprocable between the inner and outer cylinder walls, there being passages leading to and from the outer ends of the cylinders, and means for holding the pistons against rotation.

A compressor for pulsator systems comprising a rotary screw, means providing inner cylinder walls about the screw, means providing outer cylinder walls concentrically around the inner cylinder walls and opposed pistons threadedly connected to the screw reciprocable between the inner and outer cylinder walls, there being passages leading to and from the cylinders, the threaded connection between the pistons and the screw being capable of telescoping within the inner cylinder walls.

6. A compressor for pulsator systems and the like comprising means providing a double-ended cylinder, a rotary screw extending therethrough, means providing inner cylinder walls extending inwardly from the ends of the cylinder, opposed pistons threadedly connected to the screw so as to be reciprocable thereby fitting between the inner cylinder walls and the outer walls of the cylinder, and means for conveying fluid to and from the ends of the cylinder.

'7. A compressor for pulsator systems and the like comprising means providing a double-ended cylinder, a rotary screw extending therethrough, means providing inner cylinder walls extending inwardly from the ends of the cylinder, opposed pistons threadedly connected to the screw so as to be reciprocable thereby fitting between the inner cylinder walls and the outer walls of the cylinder, means for conveying fluid to and from the ends of the cylinder, and means for fastening the pistons together.

8. A compressor for pulsator systems and the like comprising means providing a double-ended cylinder, a rotary screw extending therethrough, means providing inner cylindrical walls extending inwardly from the ends of the cylinder around the screw, a piston having hub portions threaded to the screw capable of telescoping within the inner cylinder walls, means for preventing rotation of the piston, and means on the piston providing seals between the inner cylindrical walls and the outer walls of the cylinder.

9. A compressor for pulsator systems and the like comprising means providing a double-ended cylinder, a rotary screw extending therethrough, means providing inner cylindrical walls extending inwardly from the ends of the cylinder around the screw, a piston having hub portions threaded to the screw capable of telescoping within the inner cylinder walls, means for preventing rotation of the piston, means on the piston providing seals between the inner cylindrical walls and the outer walls of the cylinder, the piston being formed of opposed parts that are shimmed apart.

10. A compressor for pulsator systems and the like comprising a rotary screw, means providing annular cylinders about the screw having inner walls about the screw concentric with relation thereto, a nut on the screw reciprocable upon rotation of the screw and pistons in the cylinders adapted to be forced by the nut towards the ends of the cylinders, there being passages to and from the ends of the cylinders.

11. A compressor for pulsator systems and the like comprising a rotary screw, means providing annular cylinders about the screw having inner walls about the screw concentric with relation thereto, a nut on the screw reciprocable upon rotation of the screw, and pistons in the cylinders adapted to be forced by the nut towards the ends of the cylinders, there being passages to and from the ends of the cylinders through the cylinder heads thereof.

12. A compressor for pulsator systems and the like comprising means providing opposed annular cylinders having inner walls concentric with respect to their outer walls, and stationary with respect thereto, a rotary screw extending longitudinally within the inner walls of the cylinders, a nut on the screw, annular pistons within the cylinders and means whereby upon reciprocation of the nut the pistons may be forced toward the ends of their respective cylinders, there being provision for ingress and egress to the cylinders.

13. A compressor for pulsator systems and the like comprising means providing opposed cylinders, means extending inwardly from the ends of the cylinders providing inner cylinder walls concentric with respect to the outer walls thereof, annular pistons reciprocable in the cylinders, and means extending into the cylinders within the inner walls thereof operatively connected to the pistons for moving them in their respective cylinders, there being inlets and outlets to and from the cylinders.

14. A compressor for pulsator systems and the like comprising means providing opposed cylinders, means extending inwardly from the ends of the cylinders providing inner cylinder walls concentric with respect to the outer walls thereof, annular pistons reciprocable into the cylinders and a rotary screw extending through the cylinders disposed within the inner cylinder walls thereof, and means threadedly connecting the pistons to the screw whereby upon rotation of the screw the pistons may be moved in their respective cylinders, there being inlets and outlets to and from the cylinders.

15. A compressor for pulsator systems and the like comprising means providing opposed cylinders, means extending inwardly from the ends of the cylinders providing inner cylinder walls concentric with respect to the outer walls thereof, annular pistons reciprocable into the cylinders and a rotary screw extending through the cylinders disposed within the inner cylinder walls thereof, each piston having a hub portion telescoping into the inner cylinder wall providing means and threadedly engaging the screw whereby upon rotation of the screw the pistons may be moved in their respective cylinders, there being inlets and outlets to and from the cylinders.

16. A compressor for pulsator systems and the like comprising means providing opposed cylinders, means providing a central hub structure therebetween, piston heads having skirts telescopically mounted upon the hub structure, and freely slidable outwardly thereon, means for moving the hub structure, there being inlets and outlets to and from the cylinders, said pistons being annular, and means providing inner cylinder walls extending inwardly from the cylinder heads fitting against the interior surfaces of the pistons.

' CHARLES ULEN BALLARD. 

